MIGRATE: fix fd leak due to missing close on error.

src/migrate.c

@@ -158,6 +158,7 @@ void migrateCommand(redisClient *c) {
         return;
     }
     if ((aeWait(fd,AE_WRITABLE,timeout*1000) & AE_WRITABLE) == 0) {
+        close(fd);
         addReplySds(c,sdsnew("-IOERR error or timeout connecting to the client\r\n"));
         return;
     }